Portions of this disclosure are described in terms of, e.g., encoded signals for digital designs, product packaging (sometimes just referred to herein as “packaging” or “package”) and other objects. These encoding techniques can be used, e.g., to alter or transform how color inks are printed on various physical substrates. The alterations or transformations preferably result in a printed design carrying machine readable indicia on a surface of a physical object.
Various forms of signal encoding (or “embedding”) include, e.g., “steganographic encoding” and “digital watermarking.” Digital watermarking is a process for transforming physical or electronic media to embed a machine-readable code (or “auxiliary data”) into the media. In some cases the media is modified such that the embedded code is obscured, yet may be detected through an automated detection process. Digital watermarking is often applied to electronic or physical objects such as printed objects, images, audio signals, and video signals. However, it may also be applied to other types of objects, including, e.g., product packaging, electronics such as circuit boards and CPUs, stickers, logos, product hang tags, line-art, software, multi-dimensional graphics models, and surface textures of such objects.
In this document we use the terms “digital watermark” and “watermark” (and various forms thereof) interchangeably.
Auxiliary data embedding systems typically include two components: an encoder (or embedder) that embeds the auxiliary signal in a host image or object, and a decoder (or detector) that detects and reads the embedded auxiliary signal from the host image or object. The encoder may embed the auxiliary signal by altering or transforming a host image or object to carry the auxiliary data. The detection component analyzes a suspect image, object or signal to detect whether an auxiliary signal is present, and if so, extracts or reads information carried in it.
Several particular digital watermarking and auxiliary data embedding techniques have been developed. The reader is presumed to be familiar with the literature in this field. Particular techniques for embedding and detecting imperceptible digital watermarks are detailed in the assignee's patent documents including US Published Patent Application No. 20150156369; U.S. patent application Ser. No. 14/725,399, filed May 29, 2015 (now U.S. Pat. No. 9,635,378), Ser. No. 14/724,729, filed May 28, 2015 (published as US 2016-0217547 A1), and Ser. No. 14/842,575, filed Sep. 1, 2015 (published as US 2017-0004597 A1); International Application No. PCT/US2015/44904, filed Aug. 12, 2015 (published as WO 2016025631 A1) and U.S. Pat. Nos. 7,054,461, 7,286,685, and 9,129,277. Related technology is detailed in Assignee's U.S. patent application Ser. No. 15/073,483, filed Mar. 17, 2016 (published as US 2016-0275326 A1). Each of the patent documents mentioned in this paragraph are hereby incorporated herein by reference in its entirety, including all drawings and any appendices.
One aspect of the disclosure is a digital watermark embedding apparatus. The apparatus includes: memory for storing data representing a digital image; one or more processors configured for transforming the data by embedding a digital watermark therein, the digital watermark comprising a synchronization component and a message component; one or more processors configured for: attacking the transformed data to yield altered, transformed data; analyzing the altered, transformed data to obtain detectability measures therefrom, a first detectability measure comprising a measure corresponding to the synchronization component strength, and a second measure comprising a measure corresponding to the message component strength; and based on a combination of the first detectability measure and the second detectability measure, predicting—along one or more swipe paths—a likelihood that the transformed data, once printed on a physical substrate, will be detectable from optical scan data representing such.
The synchronization component may include a plurality of peaks in a transform domain, and the first detectability measure comprises a measure representing such peaks relative to their neighborhood. The message component may include a signature, and the second detectability measure comprises a relationship between embedded information and detected information.
The embedding apparatus may further include a re-embedding module that is activated when the predicted likelihood falls below a predetermined level, the re-embedding module further transforming the transformed data to increase digital watermark strength or coverage area.
The embedding apparatus may further include a mapping module, the mapping module configured to generate a multi-color map which represents watermark detection of the transformed data. The multi-color map may include probability indicators for the one or more swipe paths.
Another aspect of the disclosure is directed to an apparatus comprising: a display; memory for storing data representing a digital image; one or more processors configured for transforming the data by embedding digital watermarking therein, the digital watermarking comprising a synchronization component and a message component; one or more processors configured for attacking the transformed data to yield altered, transformed data; means for analyzing the altered, transformed data to obtain detectability measures therefrom, a first detectability measure comprising a measure corresponding to the synchronization component strength, and a second measure comprising a measure corresponding to the message component strength; means for predicting, based on a combination of the first detectability measure and the second detectability measure, a likelihood that the transformed data, once printed on a physical substrate, will be detectable from optical scan data representing such, such likelihoods being predicted along one or more swipe paths; and a graphical user interface for causing said display to display a multi-color map which represents watermark detection of the transformed data. The multi-color map may include probability indicators for the one or more swipe paths.
In one example, the means for analyzing and the means for predicting comprise one or more application specific integrated circuits (ASIC). In another example, the means for analyzing and the means for predicting comprise one or more specifically configured electronic processors. Of course, other examples are evident from the following description.
In still another aspect, a system is described to include: memory for storing data representing a color image; one or more processors configured for: transforming the data by embedding digital watermarking therein; analyzing the transformed data to obtain detectability measures therefrom, and generating a signal detection robustness map using the detectability measures, the robustness map visually indicating areas having more detectability capability and areas having relatively less detectability capability of the digital watermarking; and masking the color image with the robustness map to yield a final robustness image, the final robustness image comprising original color information corresponding to image areas having detectability capability and greyscale information corresponding to image areas having relatively less detectability capability.
Yet another aspect described is a method comprising: obtaining a digital watermarked color image; converting the digital watermarked color image to greyscale, said converting yields a greyscale image; modifying the greyscale image's opacity to a percentage less than 100% opacity, said modifying yielding a modified greyscale image; overlaying the modified greyscale image onto a white or light background; masking the digital watermarked color image with a robustness map, the robustness map indicating detectability of the digital watermarking per image pixel or groups of image pixels, said masking yielding a masked color image; overlaying the masked color image on top of the modified greyscale image to yield a final robustness image, in which the final robustness image comprises original design colors of the digital watermarked color image for those image areas having a higher probability of digital watermark detection and comprises grey information for those image areas having a relatively lower probability of the digital watermark being detected; and displaying the final robustness image on a computer monitor or display including displaying original design colors and grey.
Another aspect is an image processing method including: obtaining an image comprising a plurality of color separations or channels, in which the image comprises at least a 1D or 2D barcode represented therein and plural encoded signals encoded therein, the 1D or 2D barcode comprising a first plural-bit code and the plural encoded signals comprising a second plural-bit code; first analyzing data representing the image to decode the 1D or 2D barcode, said first analyzing yield the first plural-bit code; for each of the plurality of color separations or channels, second analyzing data representing the image to decode the encoded signal, said second analyzing yielding plural instances of the second plural-bit code; determining whether the plural instances of the second plural-bit code conflict with the first plural-bit code; for each conflict, providing information associated with a spatial location of the conflict relative to the image.
In the image processing method the obtaining may occur prior to a printing plate manufacture process.
In the image processing method the first analyzing data representing the image to decode the 1D or 2D barcode may operate on nonadjacent scanline data from the image.
In the image processing method, prior to the second analyzing, the method may include segmenting at least a portion of the image into a plurality of blocks, in which the second analyzing operates on individual blocks from the plurality of blocks for each of the separations or channels.
In the image processing method, the first plural bit code and the second plural bit code may include data representing a UPC code or a GTIN code. (We use the terms “plural bit” and “plural-bit” interchangeably herein.)
In the image processing method, the information associated with the spatial location may be formatted as a conflict map, where the conflict map includes a graphical box or highlight for a spatial location of the conflict relative to the image.
Another aspect of the disclosure is an image processing apparatus including: electronic memory for storing an image, the image comprising a plurality of color separations or channels, in which the image comprises at least a 1D or 2D barcode represented therein and an encoded signal encoded therein, the 1D or 2D barcode comprising a first plural bit code and the encoded signal comprising a second plural bit code; a barcode module configured for analyzing data representing the image to decode the 1D or 2D barcode to obtain the first plural bit code; a decoder module configured for analyzing each of the plurality of color separations or channels to decode the encoded signal to obtain the second plural bit code; a comparator module configured for comparing the second plural bit code with the first plural bit code for a conflict; and a results module configured for producing a conflict map, the conflict map comprising an identification of a conflict, and a spatial location of the conflict relative to the image.
Further aspects, features and advantages will become even more apparent with reference to the following detailed description, claims and accompanying drawings.